Illinois taxpayers are set to see their income tax rate lowered at the start of next year.

But not if the leadership of the DuPage Mayors and Managers Conference has anything to say about it.

In a May 1 letter to members that was obtained by the Daily Herald, the head of the Oak Brook-based agency urges municipal leaders to support keeping the state’s income tax rate at 5 percent to curry future “political capital” and possibly increase the local share of the income tax revenue.

“More active support would result in even more political leverage on (the Local Government Distributive Fund) and other current and future issues,” the agency’s executive director, Mark Baloga, wrote in the letter.

Baloga wrote that 13 of the 20-plus-member board of directors voted 9-4 Thursday to support continuing the 5 percent tax rate. He would not say who voted or how they voted.

Critics blasted the effort by a taxpayer-funded agency to support keeping the income tax rate at 5 percent.

“You’re paying property taxes so these folks can go out and try and increase your income taxes,” said Kristina Rasmussen, executive vice president of the Illinois Policy Institute, a conservative organization that tracks and analyzes government spending. “It’s despicable.”